1. Field of the Invention
The present invention relates to a motion guide device, and more particularly to a motion guide device including a bearing device having a number of cylindrical roller members disposed between two members that are movable relative to each other and having a number of spacers disposed between the cylindrical roller members for suitably spacing the cylindrical roller members from each other.
2. Description of the Prior Art
Typical motion guide devices, such as linear motion guide devices, ball screw devices, ball bearing devices or the like comprise two members that are movable relative to each other, a number of ball bearing members disposed between the two sliding members for suitably spacing the two sliding members from each other and for allowing the two sliding members to be smoothly moved relative to each other.
For allowing the ball bearing members to be suitably spaced or separated from each other, a number of spacers may further be provided and disposed between the ball bearing members for suitably spacing the ball bearing members from each other and for allowing the ball bearing members to be suitably moved or slid along the ball rolling passages that are formed between the two movable or slidable members.
For example, U.S. Pat. No. 1,405,894 to Borg discloses one of the typical ball units also comprising a number of ball bearing members disposed between two movable or slidable members for bearing and facilitating the relative sliding movement between the two movable or slidable members, and a number of spacers disposed between the ball bearing members for suitably spacing the ball bearing members from each other.
However, the ball rolling passages that are formed between the two movable or slidable members include a helical or curved structure that the ball bearing members may also be inclined relative to the spacers, but the spacers of the Borg reference may not be tilted relative to the ball bearing members such that the ball bearing members and the spacers may have a good chance to be interfered with each other.
U.S. Pat. No. 3,606,504 to Wojciochowski discloses another typical linear motion guide device comprising a number of ball bearing members disposed between two members that are movable relative to each other, and a number of spacers disposed between the ball bearing members for suitably spacing the ball bearing members from each other and for preventing the ball bearing members from interfering with each other.
However, the spacers may not be tilted relative to the ball bearing members such that the ball bearing members and the spacers may have a good chance to be interfered with each other.
U.S. Pat. No. 4,896,974 to Shimizu, U.S. Pat. No. 6,575,632 to Kawaguchi et al., U.S. Pat. No. 7,625,120 to Pan et al., and U.S. Pat. No. 7,640,820 to West et al. disclose several further typical motion guide devices each also comprising a number of ball bearing members for being disposed in a ball rolling passage formed by a ball rolling groove formed to a screw shaft and a loaded ball rolling groove formed to a nut, and a number of spacers disposed between the ball bearing members in the ball rolling passage.
However, the spacers are provided for engaging with the ball bearing members, but may not be used for engaging with the cylindrical roller members.
The present invention has arisen to mitigate and/or obviate the afore-described disadvantages of the conventional linear motion guide devices, ball screw devices or ball bearing devices.